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By C. Cassios

The paper covers the principles of Silver & Baryte Ores Mining Company (S&B) integrated Environmental Impact Assessment study for the whole of the extractive activity at the Fokida prefecture, over a time horizon of a quarter of a century. More specifically the paper includes: - The investigation and the evaluation of the environmental and socioeconomic variables of the specific area of concern. - The identification of the present and future impacts of the extractive activity. - An evaluation of the results of related reclamation activities. - Activity planning following a holistic approach, based on the principles of Sustainable Development, including environmental, social and economic aspects. - The monitoring of the procedure?s implementation.

Jan 1, 2003

By Athorn Mary-Lee, Randall A. Snowdon

During the development of the Selby Coalfield, UK, a Robbins full-face tunnel boring machine (TBM) and a Thyssen Titan roadheader were used to drive a pair of parallel spine roadways. This paper presents a summary of the comparative operational and cutting performance of both the Titan road- header and the Robbins TBM. Statistical techniques were employed to identify relations between machine performance and geotechnical parameters.

Jan 1, 1986

By Ahmed A. El-Saie

To reduce the problem of overbreak and its associated added costs, a new technique is proposed to make a slot around the tunnel profile in hard rock. The Finite Element Method was used to investigate the effect of the slot on the stress field and deflection of the tunnel core. Beam theory was also applied to calculate the stresses and deflections of a slotted tunnel for several different slot depths.

Jan 1, 1981

By John C. Balla

The Spar Lake deposit is located in northwestern Montana, approximately 27 km (17 miles) south of Troy, MT, under Mt. Vernon. The deposit is a stratiform, stratabound copper-silver deposit occurring in the Revett Formation of the Proterozoic Belt Supergroup. Distribution of known sandstone-type deposits in the Revett Formation is shown in Fig. 1.

Jan 1, 1991

By Lynn B. Hales, Randy Ynchausti

Expert systems are now being used effectively to streamline and improve the performance of supervisory computer control strategies. Their advantages have led to use in both batch and continuous applications. Expert systems in the context of real-time process control, will be defined and examples of their successful implementation in autogenous, semi-autogenous and ball mill grinding circuits will be discussed.

Jan 1, 1990

By William J. Francart

In 2003, MSHA initiated a survey of the 11 Coal Mine Safety and Health Districts to develop a database for the implementation of Atmospheric Monitoring Systems (AMS) in underground coal mines. Mine operators continue to realize the benefits of improved fire detection capabilities, as the number of mines using the systems, as well as the percentage of mines, continues to increase. Fire detection data and new technology implemented in underground coal mines is discussed as well as regulatory compliance, diesel exhaust considerations and hydrogen interference in carbon monoxide detection.

Jan 1, 2005

By J. H. Heintz

This paper discusses the law as it relates to appraising operational mining properties in the context of a takings claim. Topics include the need for valuation expertise, the differences between de jure and de facto takings, an overview of the law of condemnation, including jurisdictional issues, and defining your strategic options according to the controlling statute. State condemnation law varies by jurisdiction and just compensation can be calculated by comparable sales unit-times-price, before ¬after-valuation, capitalization of income and discounted cash flow methods. Takings under Federal laws are reviewed, as is the necessity of assembling a team including attorneys, valuation experts including a mineral appraiser, a real estate appraiser, economists and geologists.

Jan 1, 2002

By P. M. Lin

The problem of surface subsidence over abandoned mine lands is becoming more common due to the development of housing in suburban areas of abandoned mined lands. Subsidence can induce damage to estate properties, engineering structures and the environment. Houses, buildings, roads and utility pipelines may be fractured or broken or may collapse due to subsidence. The ground surface may be depressed and sink gradually or suddenly. The surface and subsurface water flow may be disrupted causing a change in flow pattern or depression of the water table. However, techniques for predicting abandoned mine subsidence are not yet well developed. Presently, one cannot predict when and where mine subsidence will occur. People have to wait until it occurs and then apply a suitable measure to remedy the damages.

Jan 1, 1990

By Z. Eisenstein, H. K. Heinz, F. M. Kuwajima

Due to its complex rheological behaviour, shotcrete induces a ground-structure interaction that differs significantly from other types of tunnel linings. For the same reason, the instrumentation of shotcrete linings presents special problems, particularly when it comes to estimating the stresses transferred to the lining during construction. The shotcrete characteristics which affect the stress distribution are initially discussed. Measurements obtained in a recent soft ground tunnel are also presented. The conclusions are aimed at introducing practical recommendations for the design of tunnels where shotcrete is used as initial and/or final support.

Jan 1, 1991

By A. C. Lyons

The presentation describes the history, preliminary report, site investigation, including examination of old records, design of tunnel including choice of levels, alternative linings and working sites, the preliminary contract involving shaft sinking on the site of the Tower Block; design modifications, the main contract, including shaft sinking, ground treatment, compressed air installation, machine tunnelling, tunnelling enlargements for chambers, waterproofing and equipment.

Jan 1, 1981

By William F. Riggs

The characteristics of frothers can often be determined by the proper selection of various chemical groups. There are three basic groups utilized in the application of frothers. These are alcohols, polyglycol ethers, and polyglycols. Some of the chemical groups are separated in subgroups. Each chemical group provides particular characteristics which affect load support, bubble diameter, water retention, air dispersion, and kinetics of froth formation. These chemical groups may be preblended in various percentages to optimize frother characteristics for a particular ore deposit.

Jan 1, 1986

By W. W. Roberts

Key elements to the successful excavation and support of the Forest Glen Station and Tunnels for the Washington Area Metropolitan Transit Authority are discussed. Excavations encompassed a twin-vault station; 2339.3 m (7675 feet) of conventional drill and shoot tunnel; and 810.8 m (2660 feet) of mixed faced tunnel. The use of dewatering, boom type continuous miner and shotcrete in the mixed faced tunnel, along with hydraulic drills, bolts, and shotcrete in the rock tunnels and station proved to be effective methods.

Jan 1, 1983

By R. J. McGregor

The Internet has revolutionized worldwide communications. Any real or perceived mining incident or environmental spill, no matter how small or remote, can become a disaster of "biblical proportions" through the judicious use of the Internet by environmental and anti-mining groups. In addition, mining companies' own Web sites and unofficial message boards can provide plenty of additional ammunition to the anti-mining forces. This paper explores how the Internet and readily available information are used by anti-mining groups active on the Web.

Jan 1, 2001

By Earle J. Klohn

Tailings disposal has rapidly become an area of increasing importance to both existing and planned mining operations. In recognition of the significance of this topic, MINING ENGINEERING is presenting a series of articles on tailings disposal. The first, published in June, outlined some site criteria that influence tailings disposal and some of the design options available to meet these criteria. The following article explores in more detail important design criteria for tailings dams and provides several case study illustrations.

Jan 7, 1981

By Ian Kilgour

The development of the Escondida concentrator is described, from the design of the original 35,000 tpd concentrator through successive expansions and modifications to the 115,000 tpd plant currently under construction. Operating problems, and the steps taken to overcome them, are briefly discussed. Reasons for key equipment choices and flowsheets modifications in the expansions are explained, with some emphasis on the flotation circuit.

Jan 1, 1995

By D. L. Petersen, C. R. Nelson, P. M. Bergson, B. K. Nelson

Membrane waterproofing systems in large tunnels cause the partial decoupling of the concrete liner from the rockbolted and shotcreted reinforced rockmass. This decoupling leads to a loose fit of the liner in the excavation when shrinkage from cooling and moisture loss occurs. This increases tensile stresses which require either the addition of reinforcing steel in excess of common European practice or the potential for liner cracking. Hot weather concrete placement and cold weather service conditions increase the magnitude of the problem, while creep of the rockmass reduces it. Contact grouting also reduces, but does not eliminate, the problem.

Jan 1, 1991

By Jack C. Stuart, Robert L. Obradovic, Allen J. Hulshizer, Anthony J. Stewart

Two deep bedrock tunnels, extending over a mile into the Atlantic Ocean, to provide the cooling water requirements for the Seabrook Station represent a major tunneling venture. This paper provides an outline and discussion of the planning and construction work associated with developing of the land riser and work shafts and the conventionally excavated tunnel station area.

Jan 1, 1979

By Yoginder P. Chugh

The mining methods used at many opencast brown coal mines in Poland and the German Democratic Republic are not used in the US to any extent. Using bucketwheel excavators, bucket chain excavators, and mobile conveyor bridges, the mining techniques may offer efficient, economic alternatives for operators in the US. These mining methods were observed during visits to several open-cast brown coal mines in Eastern Europe over the past two years. Some of them may be particularly attractive for the large lignite mines being planned in North Dakota and Texas.

Jan 11, 1980

By M. Pantazidou

Motivated by recent EU legislation already entered into force or in preparation, this article aims at offering glimpses of the future landscape in the area of subsurface protection against contamination from point sources. Towards this end, it discusses the most salient parts of legislation for the protection of water resources. It then presents results from the wide consultation rounds organized by the European Commission in order to both receive input and help make all opinions heard on the issue of soil protection. Finally, it introduces key provisions of the recent legislation on environmental liability. From the above pieces of legislation, this paper highlights the elements that concern specifically the protection of the subsurface against spills of hazardous wastes from point sources and the requirements for subsurface restoration.

Jan 1, 2005

By C. Ostrowski, Z. Fajklewicz, K. Jakiel

Results of the application of the micro-gravity method in predicting rock bursts and rock mass deformations are discussed. Research was done in the Daisy black coal mine, Upper Silesia, Poland, during 1979-1980. At that time, microgravity investigations helped increase the safety of coalbed exploitation in progress. During the first stage of exploitation, a mining shock of 107 J energy was predicted in a region where 40 miners worked.

Jan 1, 1987